Do you know how to deal with the silver skin of coffee? how is the silver skin removed from the roasted coffee?

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Silver Skin/Chaff: there is a thinner film inside the parchment that wraps the coffee beans. Because the color is glossy and silvery, people used to call it "silver skin". This layer of silver will fall off during baking. Usually when you grind the coffee, you find some silver crumbs in the coffee powder. These crumbs are the silver skins that fail to peel off the coffee beans during baking.

There is a saying in Coffee Coffee that if we roast and heat the coffee beans, the dried (sun-dried) coffee beans will peel off a lot of silver, while the water-washed coffee beans are much less. When we look at the central concave line of coffee beans, if we retain a lot of white silver skin, the coffee beans processed by water shampoo are more likely.

Water content

The water content of water-washed coffee is 12% 13%, while that of dry (sun-dried) coffee is 1112%. General coffee beans show different colors due to their different water content, with higher water content being green or cyan, and less brown or near white. Therefore, the washed coffee beans show a darker green.

Is the silver skin in good condition?

In the process of processing, the washing method usually removes the silver skin from the coffee beans, showing a special luster, but the law of drying and refinement only takes off the coffee shell, and the silver skin is still intact.

Baking degree

Different processing methods use different degrees of baking, the effect is also different. In general, if the water-washed coffee beans have not been deeply roasted, the residual silver skin of the central line still exists. Although the silver skins of dry coffee beans are intact during processing, they are all gone after baking. The deeper the roasting, the darker the coffee beans will be.

The outer silver skin of the beans in the sun is relatively more, and it takes off more thoroughly when baking, so it is relatively less when grinding; there is more silver skin in the beans washed in water, and there will be a lot of residue after baking and more when grinding. Of course, it is directly related to the baking degree. The deeper the baking, the cleaner the silver skin will take off.

If there is too much silver skin, it will taste astringent, but if the raw bean treats the silver skin too much, it will lead to a decrease in flavor.

Moreover, there must be silver skin on the central line of washed beans, but the problem is that that part may not produce obvious astringency, so don't pick out the silver skin completely.

A good electric bean grinder has the function of automatically removing silver skin. if you grind it by hand, the silver skin will be blown off by maximum rough grinding and then fine grinding. No silver peel is a little astringent but does not affect the overall taste of the coffee.

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